title: 2,4-Di-bromo-1,3-dihy-droxy-9H-xanthen-9-one.
abstract: The title compound, C13H6Br2O4, derived from xanthone, a fundamental structural framework of active ingredients in many medicinal plants, and was synthesized by bromination of 1,3-di-hydroxyxanthen-9-one with N-bromo-succinimide. The mol-ecular conformation is essentially planar, the dihedral angle between the benzene rings being 1.1 (4)°. This conformation is favorable for the formation of an intra-molecular O-H⋯O hydrogen bond between a hy-droxy group and the xanthone carbonyl group. In the crystal, mol-ecules are associated into chains along the b-axis direction via C=O⋯H-O hydrogen bonds involving the other hy-droxy group.
authors.affiliation: Key Laboratory for the Chemistry & Molecular Engineering of Medicinal Resources, Ministry of Education of China, School of Chemistry & Chemical Engineering, Guangxi Normal University, Guilin, 541004, People's Republic of China ; Department of Pharmacy, Youjiang Medical University for Nationalities, Baise 533000, People's Republic of China.
authors.forename: Shi-Wen
authors.initials: SW
authors.lastname: Huang
authors.forename: Zheng-Min
authors.initials: ZM
authors.lastname: Yang
authors.forename: Fu-Ping
authors.initials: FP
authors.lastname: Huang
authors.forename: Jiang-Ke
authors.initials: JK
authors.lastname: Qin